It is not yet clear what substance was in the water. Local police have visited the site, and the Guarani are waiting for the results of their investigation.

Survival International’s Director Stephen Corry said today, ‘For too long the Guarani have borne the brunt of a sustained, malicious, and inventive campaign of terror to keep them off the land that rightfully belongs to them. The perpetrators of this latest cruel and perverse act should be brought to justice. The federal government must urge local police to carry out a thorough and unbiased investigation.’